The present invention relates to electrical power generators, and more particularly to electrical power generators that are compatible with battery powered portable appliances.
Current art portable electrical appliances, such as flash lights, remote controllers, pagers, cellular phones and laptop computers, require batteries as their power sources. Compared to electrical appliances that require power cords, these portable appliances are far more convenient to use. However, batteries run out of charge, limiting the time one can use certain appliances. Cameras run out of batteries when pictures need to be taken. Laptops shut down during important presentations. The constant need to replace or to re-charge drained batteries is therefore a source of inconvenience for current art portable electrical appliances.
Many inventions have been developed to address this problem. Campagnuolo et al. disclosed a portable hand-cranked electrical power generator in U.S. Pat. No. 4,227,092, and a leg driven power generator in U.S. Pat. No. 4,746,806. Those power generators were “lightweight” at the time of the inventions, but are far too heavy for today's portable appliances. In U.S. Pat. No. 5,905,359, Jimena disclosed a relatively small electrical power generator installed in a flash light. This power generator used the batteries in the flash light as a flying wheel to store kinetic energy, and used magnetism to convert rotational motion of the flying wheel into electrical energy. Users must purchase special apparatuses installed with rotational batteries and power generators in order to utilize Jimena's invention. Haney et al. disclosed a manually-powered portable power generator. The apparatus comprises of a manually operable air pump that provides a compressed flow of air used to rotate an electrical power generator. Users must use a specially designed air pump and power generator to use the invention.
These inventions are all valuable methods to provide electrical power. However, none of them have been widely used. The major reason is that they miss the key value of portable appliances. The most important advantage of portable appliances is convenience. If the users need to purchase special apparatuses or wear special gears to charge portable devices, the additional inconvenience defeat the original purpose of portable appliances. Most users would rather use conventional batteries because of availability and convenience. To be popularly used, portable power generators must be made more convenient to use than conventional batteries. In order to achieve those goals, we believe that portable electrical power generators must be compatible with existing battery powered appliances. Such power generators should be as easy to use as conventional batteries, and be more convenient to replace or recharge.
Batteries have other problems. Much more energy is used to manufacture batteries than actually provided by the battery. When batteries are used up and discarded, the chemicals in the batteries pollute the environment. Typical battery usage is therefore a terrible pollution source. There are environment-friendly methods of generating electrical power such as solar cells or wind mills. Van Breems disclosed an apparatus to convert tidal energy into electrical energy in U.S. Pat. No. 6,833,631. However, these environment-friendly methods provide insignificant amounts of energy compared to overall energy consumption. Due to cost considerations, human beings are still burning oil, building dams, building nuclear power plants, and using energy-inefficient batteries, polluting the planet to feed energy-hungry human societies. Although those environment-friendly methods have been available for decades, they will not be fully utilized unless their cost is comparable to polluting methods. It is therefore highly desirable to provide cost efficient, environmentally friendly energy sources.